[35.04] High-Resolution Studies of the Solar Polar Magnetic Fields

J. R. Varsik (NSO/SP), P. R. Wilson, Y. Li (Univ. of Sydney)

Most observations of the polar magnetic fields of the Sun
have been at relatively low resolution. High-resolution
studies of the polar fields offer new insight into their
evolution. We show that near sunspot maximum in 1989, the polar regions
are covered with several unipolar regions, each region
containing magnetic knots of both polarities. These knots
have average lifetimes greater than 7 hours but less than 24 hours.
In 1995, after the polar field reversal was complete, each pole
exhibits one dominant polarity, and
the dominant polarity knots are in a ratio of 5:1 to the opposite
polarity. By measuring the displacement of magnetic knots over
a 7 hour period a rotation rate can be determined which is consistent
with the Snodgrass (1982) relation determined by cross correlations
of Mt. Wilson magnetograms.
Most knots are not seen in magnetic bipoles either when the overall
polar fields are mixed or when one polarity is dominant.